Researchers clone gene that regulates fruit size

Esther van der Knaap (Photo by Ken Chamberlain)WOOSTER, Ohio -- Do you enjoy big, plump tomatoes? If so, you should give thanks to a gene that arose thousands of years ago as early farmers in South America began domesticating this popular fruit, according to Ohio State University crop scientists.

The discovery was reported Sept. 30 in the Proceedings of the National Academy of Sciences.

"This work represents an important improvement in the understanding of the regulation of fruit size and how domestication played a role in the selection of this gene," said van der Knaap, who is based on the Wooster campus of the Ohio Agricultural Research and Development Center (OARDC), the research arm of the college.

The cloned gene, known as SlKLUH, impacts fruit size by increasing cell layers and delaying ripening. According to van der Knaap, this gene promotes extra cell divisions during the process of fruit development, immediately after fertilization. These extra cell divisions lead to enlarged fruit, while the delay in ripening is likely the result of an extension of the cell division stage.